Case Presentation: A 57-year-old female with diabetes mellitus and hypertension presented for a post-operative visit 3 weeks after spinal surgery with chief complaint of new-onset left leg weakness, leg buckling when upright, and increased dependence on her walker, despite initially recovering well. Physical exam exhibited 4-5/5 strength in all tested groups except for 1-2/5 strength in hip flexion, foot dorsiflexion, and toe dorsiflexion. Sensory examination was normal. Reflexes were 2/4 except for 1/4 in Achilles bilaterally. The patient was admitted, and initial labs revealed mild hyponatremia (135) and mild normocytic anemia (hemoglobin 12.8, MCV 88.2), with no other significant findings. MRI of the lumbar, cervical, and thoracic spine, as well as the brain, were unremarkable, making metabolic causes, nerve root edema, hematoma, infection, hardware failure, and disc herniations less likely. Electromyography (EMG) indicated an acute, widespread, but asymmetric neurogenic process with features of demyelination. A lumbar puncture was performed and revealed a protein level of 192.5 mg/dL and a WBC of 2/μl. The findings were consistent with a diagnosis of acute inflammatory demyelinating polyneuropathy (AIDP), and treatment with intravenous immunoglobulin (IVIG) began. After completion of IVIG and strength improvement to 4/5 in all extremities, the patient was discharged home with plans for outpatient physical therapy, occupational therapy, and follow-up with neurology and orthopedics.
Discussion: Primary causes of motor weakness after spinal surgery include iatrogenic root injury, nerve root edema, cauda equina syndrome, surgical site infections, post-operative hematoma, and hardware failure. Initial work-up should focus on ruling out infection, metabolic etiologies, and surgical complications with CBC, CMP, and MRI. If imaging and labs are inconclusive, inflammatory myopathies, demyelinating pathologies, polyneuropathies, thyroid dysfunction, nutritional deficiencies, and psychiatric disorders should be considered. Demyelinating diseases such as multifocal motor neuropathy, sensorimotor neuropathies, inclusion body myositis, and chronic inflammatory demyelinating polyneuropathy should be included in the differential. An EMG and lumbar puncture can be useful for further evaluation of the above conditions. This patient’s final diagnosis was AIDP, a subtype of Guillain-Barre Syndrome (GBS). While GBS has been previously characterized as a post-infectious disorder, a growing body of literature identifies post-surgical GBS cases following procedures on the spine, gastrointestinal tract, heart, brain, uterus, and renal and stem cell transplantations. This case supports the view of GBS as a post-trauma disorder, where infection, a surgical procedure, or other etiologies not yet described can act as a trigger. IVIG is the preferred treatment for GBS as it blocks the GBS-specific antibodies that attack myelin and/or Schwann cells. Steroids are usually not recommended, as they are thought to inhibit the action of scavenger molecules involved in nerve regeneration.
Conclusions: When evaluating a patient for post-surgical weakness, demyelinating polyneuropathies like GBS should be considered early in the diagnostic process. This case report adds to the growing evidence that GBS can occur post-surgically, emphasizing the importance of early diagnosis to improve the patient’s time to recovery and reduce unnecessary diagnostic interventions.